As a flexible and cost-efficient scalable Internet access network, we have studied architectures, protocols, and design optimizations of the {\em Wireless Internet-access Mesh NETwork (WIMNET)}. WIMNET is composed of wirelessly connected access points (APs), where any host can basically access to the Internet through multihop communications between APs. In WIMNET, undesirable situations can often happen such that some links dominate the bandwidth while others become insufficient due to the limited shared bandwidth. To improve the performance by avoiding them, controls of activation chances for wireless links depending on their traffics are effective. Thus, previously, we have proposed the {\em Fixed Backoff-time Switching (FBS) method} for the CSMA/CA protocol, and verified the effectiveness using the {\em QualNet} simulator. In this paper, we present an implementation design of the FBS method in Linux kernel to show its practicality and investigate the performance in a real network. Our design consists of implementations or modifications of the five programs: {\em Kernel configuration}, {\em Debugfs}, {\em Minstrel}, {\em iw}, and {\em FBSdaemon}.